Implement server-suggested update check backoff

chrome/browser/android/webapk/webapk_update_manager.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_UPDATE_MANAGER_H_
 #define CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_UPDATE_MANAGER_H_
 
 #include "base/android/jni_android.h"
 #include "base/macros.h"
 
 // WebApkUpdateManager is the C++ counterpart of org.chromium.chrome.browser's
 // WebApkUpdateManager in Java. It calls WebApkInstaller to send an update
 // request to WebAPK Server.
 class WebApkUpdateManager {
  public:
   // Registers JNI hooks.
   static bool Register(JNIEnv* env);
 
   // Called after either a request to update the WebAPK has been sent, or the
   // update process fails. |success| indicates whether the request was issued
   // to the server. A "true" value of |success| does not guarantee that the
   // WebAPK will be successfully updated.
   static void OnBuiltWebApk(const std::string& id,
                             bool success,
+                            bool relax_updates,
                             const std::string& webapk_package);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(WebApkUpdateManager);
 };
 
 #endif  // CHROME_BROWSER_ANDROID_WEBAPK_WEBAPK_UPDATE_MANAGER_H_